Embodiments relate to detecting latent images and, more particularly, to detecting latent images left on a thermal dye printer film.
A thermal dye printer, dye-sublimation printer or dye-sub printer is a computer printer which employs a printing process that uses heat to transfer dye onto materials such as a plastic, card, paper, or fabric. Many consumer and professional dye-sublimation printers are designed and used for producing such items as, but not limited to, photographic prints, identification (“ID”) cards, etc.
The thermal dye printer produces continuous-tone images that look very much like photographic film. Thermal dye printers include a print cartridge that contains a cellophane covered thermal dye printer film having a plurality of stored panels of dye having the same dimensions as the page printed. There are generally four different panels for each print, one color panel each of cyan, magenta and yellow (CMY) and a final clear (K) coat panel or overcoat (O) panel that allows the printed image on special dye-receptive paper to be handled immediately without smudging.
Heat releases the CMY dyes from the film. The paper and film are passed together under the print head for each color panel, so that the process lays one color at a time from the film. The print head may contain thousands of heating elements that produce varying amounts of heat. The hotter the element, the more dye is released. By varying the temperature, selectable shades of each color can be overlaid on top of each other. The dyes blend into continuous-tone color image in the paper. The imaged paper is then sealed by the protective final clear overcoat (K) layer to provide water-resistant and UV blocking barrier that also prevents smudging, helping to ensure the preservation of images.
Counterfeiters can use a variety of different printers to print counterfeit bills/currency. Laser printers and inkjet printers have been used for this purpose. A problem with laser printers and inkjet printers for counterfeiting is that they cannot replicate the government-issue hidden strips. It is known that thermal dye printers using a first and second printing process can print bills that include the government-issue strips.
Once the film for a thermal dye printer is used, a latent image of what was printed is usually left on the film. In order to capture and successfully prosecute counterfeiters, a method and system to obtain latent images left on a thermal dye printer film is desired. However, such film is usually crinkled and crushed which makes acquiring images from the film that much more difficult. Furthermore, if handled improperly, the film is likely to tear or rip. Thus, there is a need for any such method and system to be able to acquire a latent image from such film that may be crinkled, crushed, torn, or fragile enough to tear.